Design of Awa Shirasagi Ohashi Bridge

The Awa Shirasagi Ohashi Bridge, which includes novel structural systems, was recently constructed in Tokushima, Japan (Figure 1). There were a number of severe design constraints for the project.
The bridge is located in a very environmentally sensitive area. The site is also in a seismic region and is frequently struck by typhoons. Furthermore, the bridge was to be founded on soft alluvium, and to be constructed to a tight budget.
These exceptionally challenging constraints led engineers to adopt a novel combination of structural forms, including the ‘cable egret’ cable truss system, an improved form of the permanent tubular steel pile cofferdam foundation and a steel- concrete composite sandwich slab deck.